Generally, a heat-insulating housing of a refrigerator is formed of a layered body including a steel (including iron and cast iron) plate as an outer wall material, a resin plate as an inner wall material and a heat insulator interposed between the steel plate and the resin plate. The heat insulator is made of a foamed resin such as urethane foam, and chlorofluorocarbons conventionally have been used as a foaming gas therefor. Since chlorofluorocarbons may destroy the ozone layer, it is necessary to collect and prevent them from diffusing into the air at the time of disposing of a refrigerator. It also is desired that the steel plate and the resin plate should be collected for recycling. Furthermore, in some cases where linear objects such as pipes (for example, copper pipes) through which a refrigerant passes and electrically conductive wires are embedded in the heat insulator, it is desired that they should be separated from the heat insulator and collected.
Conventionally, a discarded refrigerator has been disassembled as follows.
First, refrigerant (for example, chlorofluorocarbons) and refrigeration oil are collected from the discarded refrigerator, and then the compressor is removed (a first separating process). The resultant heat-insulating housing of the refrigerator is put into a peeling and smashing machine. The peeling and smashing machine is provided with a rotating cylindrical body having many rotating and projecting blades on its outer periphery. The peeling and smashing machine roughly smashes the heat-insulating housing of the refrigerator into pieces having a size on the order of several cm and separates the outer wall material (steel plate), the inner wall material (resin plate), the linear object and the heat insulator (urethane foam). At this time, some of the closed-cells in the heat insulator are destroyed, thus releasing the chlorofluorocarbons. These chlorofluorocarbons are collected by equipment for collecting low-concentration chlorofluorocarbons.
The steel plate, the resin plate, the linear object and the foamed resin that have been smashed roughly are separated by a wind-power separator utilizing the difference in specific gravity or the like.
The separated foamed resin is sent to a crusher and smashed further minutely, so that remaining chlorofluorocarbons are drawn out. As a method for collecting the chlorofluorocarbons for this case, a method described in JP 2679562 B is known, for example. After the foamed resin is smashed roughly into pieces having a size on the order of several cm, it is put into a hopper and sent to a crusher. In the process where an external mechanical force is applied in the crusher so as to crush the foamed resin, closed-cells therein are destroyed. Chlorofluorocarbons released from the closed-cells and the minutely crushed resin grains are sent to a bag filter together with the air, so that a gaseous component and the resin grains are separated. When the resin grains are heated and compressed in a volume reducer, any remaining chlorofluorocarbons are squeezed out also at this time. The chlorofluorocarbons generated in the above process are sent to a condenser together with the air and cooled down, so that the chlorofluorocarbons are liquefied and separated, and then the gas that is not condensed is sent back to the hopper. In this manner, the chlorofluorocarbons contained in the foamed resin can be separated and collected without being diffused into the air.
However, the above-described disassembling method has had the following problems.
The heat-insulating housing of the refrigerator after the first separating process has to be smashed roughly into pieces having a size on the order of several cm by the peeling and smashing machine in order to separate the foamed resin and other members. At this time of rough smashing, the closed-cells in the foamed resin are destroyed, thus releasing a slight though certain amount of chlorofluorocarbons. Accordingly, a process of collecting these chlorofluorocarbons is necessary. In addition to this, since the chlorofluorocarbons are contained in the air including the roughly smashed foamed resin to be separated by a wind power, they have an extremely low concentration.
Moreover, even after minutely crushing the foamed resin, in order to separate the foamed resin grains and the released chlorofluorocarbons, a mixture thereof is sent with the air to the bag filter, so that they are separated by utilizing a wind power. Thus, since the chlorofluorocarbons are diffused in the carrier air, the concentration of the chlorofluorocarbons becomes extremely low.
As described above, in the conventional method for disassembling the refrigerator, the condensation and separation of the chlorofluorocarbons diffused in an extremely low concentration are by no means efficient. Furthermore, the equipment for carrying out these processes is large, raising equipment costs considerably.
Moreover, the peeling and smashing machine, the wind-power separator, the crusher, the bag filter and equipment attached to them generally are very large, which require a large sealed installation space and cost much.